When a rattlesnake is cornered, sometimes it becomes so angry that it bites itself.
When a man harbors hatred or bitterness in his heart he is poisoning himself just like the rattlesnake that bites itself.
"Hatred is self-punishment." - Hosea Ballou.
Ecc 7:9 (CEV): "Only fools get angry quickly and hold a grudge."
"Bitterness imprisons life; love releases it." - Harry Emerson Fosdick.
"A bitter spirit will keep you from being a better person." - Woodrow Kroll.